Hitherto, antireflection techniques have been developed to reduce surface reflection and to increase an amount of transmitted light, and have been employed in various fields including, e.g., display devices used in TVs, cellular phones, etc., and optical elements in camera lenses.
One example of the antireflection techniques is an antireflective member in which fine concave-convex irregularities (constituting an antireflection structure) are formed on an outside-light incident surface of the antireflective member at a period that is controlled to be equal to or shorter than wavelength of visible light (see, e.g., Patent Literature (PTL) 1). In such a configuration, reflection of light entering the antireflective member is suppressed by, on the basis of the principle of the so-called Motheye structure, changing the refractive index in a height direction of the concave-convex irregularities gradually from the refractive index of an incident medium to the refractive index of a substrate.